From 0f044468396f3edbe5cfba97e7563a53e397c153 Mon Sep 17 00:00:00 2001
From: Enrico Tassi <enrico.tassi@inria.fr>
Date: Fri, 14 Apr 2006 10:14:43 +0000
Subject: [PATCH] 	duplicate check for coercions when added to Db

---
 components/library/librarySync.ml | 56 +++++++++++++++++++------------
 1 file changed, 34 insertions(+), 22 deletions(-)

diff --git a/components/library/librarySync.ml b/components/library/librarySync.ml
index 9ce5801fd..2dcd6a8b9 100644
--- a/components/library/librarySync.ml
+++ b/components/library/librarySync.ml
@@ -227,29 +227,41 @@ let add_coercion ~add_composites refinement_toolkit uri =
   List.iter 
     (fun (src,tgt,uri,_) -> CoercDb.add_coercion (src,tgt,uri)) 
       new_coercions;
-  CoercDb.add_coercion (src_carr, tgt_carr, uri);
-  (* add the composites obj and they eventual lemmas *)
-  let lemmas = 
-    if add_composites then
-      List.fold_left
-        (fun acc (_,_,uri,obj) -> 
-          add_single_obj uri obj refinement_toolkit;
-          uri::acc) 
-        composite_uris new_coercions
-    else
+  if 
+    List.exists 
+      (fun (s,t,_) -> CoercDb.eq_carr s src_carr && CoercDb.eq_carr t tgt_carr)
+      (CoercDb.to_list ())
+  then
+    begin
+      assert (new_coercions = []);
       []
-  in
-  (* store that composite_uris are related to uri. the first component is the
-   * stuff in the DB while the second is stuff for remove_obj *)
-  (* 
-     prerr_endline ("adding: " ^ 
-       string_of_bool add_composites ^ UriManager.string_of_uri uri);
-     List.iter (fun u -> prerr_endline (UriManager.string_of_uri u))
-      composite_uris; 
-  *)
-  UriManager.UriHashtbl.add coercion_hashtbl uri 
-    (composite_uris,if add_composites then composite_uris else []);
-  lemmas
+    end
+  else
+    begin
+      CoercDb.add_coercion (src_carr, tgt_carr, uri);
+      (* add the composites obj and they eventual lemmas *)
+      let lemmas = 
+        if add_composites then
+          List.fold_left
+            (fun acc (_,_,uri,obj) -> 
+              add_single_obj uri obj refinement_toolkit;
+              uri::acc) 
+            composite_uris new_coercions
+        else
+          []
+      in
+      (* store that composite_uris are related to uri. the first component is
+       * the stuff in the DB while the second is stuff for remove_obj *)
+      (* 
+         prerr_endline ("adding: " ^ 
+           string_of_bool add_composites ^ UriManager.string_of_uri uri);
+         List.iter (fun u -> prerr_endline (UriManager.string_of_uri u))
+          composite_uris; 
+      *)
+      UriManager.UriHashtbl.add coercion_hashtbl uri 
+        (composite_uris,if add_composites then composite_uris else []);
+      lemmas
+    end
 
 let remove_coercion uri =
   try
-- 
2.39.2